1. Field of the Invention
The present invention relates to a counterbalance device for weight training and, more particularly, to a counterbalance device which uses an elasticity of a spring to resist a force exerted by a user.
2. Description of the Related Art
FIG. 1 shows a conventional fitness apparatus 10 used for weight training. The fitness apparatus 10 includes a plurality of counterbalancing members 14 made of cast iron which can slide on two guiding rails 15. An insertion bar 13 is inserted in middle portions of the counterbalancing members 14 and includes a plurality of holes 131 for coupling with the counterbalancing members 14 by forelocks, so that when the fitness apparatus 10 is under operation, the insertion bar 13 and the counterbalancing members 14 coupled with the insertion bar 13 are pulled upward by a steel cable 12. When a force is not exerted by a user, the uplifted counterbalancing members 14 will be moved downward. A weight of the counterbalancing members 14 is used for resisting an exerted force of the user, therefore a fitness effect can be achieved. However, the fitness apparatus 10 has the following drawbacks:
1. The counterbalancing members 14 are made of cast iron, and when they are moved downward, a loud noise is produced because they collide with each other.
2. Because physical capability of every user is different, thus the weight of the counterbalancing members 14 needs to be adjusted very often. When it is needed to adjust the weight of the counterbalancing members 14, one or more pieces of the counterbalancing members 14 is needed to be removed or added, and it is very inconvenient for dismounting or assembling. Further, the heavy weight of the counterbalancing members 14 makes it difficult to carry.